Tag Intersection -- Asymptote Gallery

🔗Asymptote Gallery Tagged by “Intersection” #102

🔗generalities-fig174

Figure generalities 174 Generated with Asymptote

Show generalities/fig1750.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Generalities
Tags : #Basis | #Path | #Intersection

size(6cm,0);

path p = (0,0){up} .. (2cm,0){up};
path q = (0,1cm){dir(-60)}..(1cm,-1cm)..{dir(60)}(2cm,1cm);

draw(p, red);
draw(q, blue);
dot(intersectionpoint(p,q));
draw(point(p, intersect(p,q)[0])--postcontrol(p, intersect(p,q)[0]), .8red,Arrow);
draw(point(q, intersect(p,q)[1])--postcontrol(q, intersect(p,q)[1]), .8blue,Arrow);

🔗generalities-fig176

Figure generalities 176 Generated with Asymptote

Show generalities/fig1770.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Generalities
Tags : #Basis | #Circle | #Intersection | #Function creation

size(6cm,0);

import math;

pair A=(0,0), B=(1,.5);
path cle=shift(1.75,2.5)*unitcircle;
pair pt, ptp;

pair project(pair pt, pair A, pair B)
  {
    return extension(pt,pt-dir(90+degrees(A-B,false)),A,B);
  }

draw(A--B);
draw(cle);

for (real t=0; t<=4; t+=.01)
  {
    pt=point(cle,t);
    ptp=project(pt,A,B);
    dot(ptp, red);
    draw(pt--ptp,dotted);

  }

🔗generalities-fig177

Figure generalities 177 Generated with Asymptote

Show generalities/fig1780.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Generalities
Tags : #Basis | #Geometry | #Intersection

size(6cm,0);

import math;

pair A=(0,0), B=(1,.5), C=(.25,1);

pair project(pair pt, pair A, pair B)
  {
    return extension(pt,pt-dir(90+degrees(A-B,false)),A,B);
  }

pair ocenter(pair A, pair B, pair C)
  {
    return extension(A, project(A,B,C), B, project(B,A,C));
  }

draw(A--B--C--cycle);

pair orth=ocenter(A,B,C);
pair Ap=project(A,B,C);
pair Bp=project(B,A,C);
pair Cp=project(C,A,B);

dot(orth, red);
dot(Ap^^Bp^^Cp);
drawline(A, orth, dotted);
drawline(B, orth, dotted);
drawline(C, orth, dotted);

🔗generalities-fig178

Figure generalities 178 Generated with Asymptote

Show generalities/fig1790.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Generalities
Tags : #Basis | #Circle | #Geometry | #Intersection

size(6cm,0);

import math;

pair A=(0,0), B=(1,.5), C=(.25,1);

pair ccenter(pair A, pair B, pair C)
  {
    pair mAB=midpoint(A--B);
    pair mAC=midpoint(A--C);
    return extension(mAB, rotate(90,mAB)*A, mAC, rotate(90,mAC)*A);
  }

draw(A--B--C--cycle);

pair circ=ccenter(A,B,C);
pair mAB=midpoint(A--B);
pair mAC=midpoint(A--C);
pair mBC=midpoint(B--C);

dot(circ, red);
dot(mAB^^mAC^^mBC);
drawline(mAB, circ, dotted);
drawline(mAC, circ, dotted);
drawline(mBC, circ, dotted);
draw(shift(circ)*scale(abs(circ-A))*unitcircle);

🔗generalities-fig179

Figure generalities 179 Generated with Asymptote

Show generalities/fig1800.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Generalities
Tags : #Basis | #Circle | #Geometry | #Intersection

size(6cm,0);

import math;

pair A=(0,0), B=(1,.5), C=(.25,1);

pair project(pair pt, pair A, pair B)
  {
    return extension(pt,pt-dir(90+degrees(A-B,false)),A,B);
  }

pair icenter(pair A, pair B, pair C)
  {
    return extension(A, A+dir(A--B,A--C), B, B+dir(B--A,B--C));
  }

draw(A--B--C--cycle);

pair ins=icenter(A,B,C);
pair iAB=project(ins,A,B);
pair iAC=project(ins,A,C);
pair iBC=project(ins,B,C);

dot(ins, red);
dot(iAB^^iAC^^iBC);
drawline(A, ins, dotted);
drawline(B, ins, dotted);
drawline(C, ins, dotted);
draw(shift(ins)*scale(abs(ins-iAB))*unitcircle);

🔗generalities-fig180

Figure generalities 180 Generated with Asymptote

size(6cm,0);
import math;

pair project(pair pt, pair A, pair B)
  {
    return extension(pt,pt-dir(90+degrees(A-B,false)),A,B);
  }


pair ecenter(pair A, pair B, pair C)
  {
    return extension(A, A+rotate(90)*dir(A--B,A--C), B, B+rotate(90)*dir(B--A,B--C));
  }

path ecircle(pair A, pair B, pair C)
  {
    return shift(ecenter(A,B,C))*scale(abs(ecenter(A,B,C)-project(ecenter(A,B,C),B,C)))*unitcircle;
  }

pair A=(0,0), B=(3,0), C=(3,4);
path tr=A--B--C--cycle;

draw(ecircle(A,B,C));
draw(ecircle(B,C,A));

pen p=linewidth(1pt);
drawline(A,B, p);
drawline(A,C, p);
drawline(B,C, p);

🔗generalities-fig185

Figure generalities 185 Generated with Asymptote

Show generalities/fig1870.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Generalities
Tags : #Basis | #Path | #Intersection

size(15cm,0);

srand(rand());
path p1 = randompath(9);
path p2 = randompath(8);
real Minx=min(min(p1).x,min(p2).x);
real Maxx=max(max(p1).x,max(p2).x);
real Miny=min(min(p1).y,min(p2).y);

pair[] inter=intersectionpoints(p1,p2);
int nb=inter.length;
for (int i=0 ; i<nb; ++i)
  {
    dot(inter[i]);
    label("$" + (string) i +"$", inter[i],N);
  }

draw(p1,.8red);
draw(p2,.8green);
label("I found " + (string) nb + " points of intersection.",((Maxx+Minx)/2,Miny),2S);

🔗generalities-fig186

Figure generalities 186 Generated with Asymptote

Show generalities/fig1880.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Generalities
Tags : #Basis | #Path | #Intersection

size(10cm,0);

pair[] self_intersection(path p, int n=100)
{
  pair[] rpair=new pair[];
  path tpath;
  real [] tpoint;
  real l=length(p);
  int i=1;
  for (real t1=0; t1<l ; t1+=l/n)
    {
      for (real t2=t1+2*l/n; t2<l; t2+=l/n)
        {
          tpoint=intersect(subpath(p,t1,t1+l/n),
                           subpath(p,t2,t2+l/n));
          if (tpoint.length == 2)
            {
              rpair[i]=point(subpath(p,t1,t1+l/n),tpoint[0]);
              ++i;
            }
        }
    }
  return rpair;
}

void dott(pair[] pt, pen p)
{
  for (int i=1 ; i<pt.length; ++i)
    {
      dot(pt[i], p);
    }
}

srand(rand());
path p = randompath(15);

pair[] inter=self_intersection(p);
dott(inter, .8red);
draw(p);

🔗generalities-fig187

Figure generalities 187 Generated with Asymptote

size(6cm,0);
path [] c;

c[1] = xscale(2)*unitcircle;
c[2] = shift((0,1))*c[1];
draw(c[1]^^c[2]);
draw(buildcycle(c[1],c[2]), .8red+4bp);

🔗generalities-fig188

Figure generalities 188 Generated with Asymptote

size(8cm,0);

path a,b,c,d;
a = (-1,-.2){up} .. tension 1.2 .. (1,-.2){down};
transform r90=rotate(90);
b = r90*a;
c = r90*b;
d = r90*c;
path bound=buildcycle(a,b,c,d);
fill(bound, lightgrey);
draw(a^^b^^c^^d,grey);
draw(bound);

🔗generalities-fig189

Figure generalities 189 Generated with Asymptote

size(8cm,0);

path a,b,c;
a = shift(1,0)*scale(2)*unitcircle;
b = rotate(120)*a;
c = rotate(120)*b;

fill(a, red);
fill(b, green);
fill(c, blue);
fill(buildcycle(a,b), red + green);
fill(buildcycle(b,c), green + blue);
fill(buildcycle(c,a), blue + red);
fill(buildcycle(a,b,c), white);

draw(a^^b^^c);

🔗generalities-fig191

Figure generalities 191 Generated with Asymptote

size(0,0);

path pt1=scale(2cm)*unitcircle;
path pt2=scale(1cm)*unitcircle;

filldraw(pt1^^pt2,evenodd+yellow+.9white);

🔗generalities-fig192

Figure generalities 192 Generated with Asymptote

size(0,0);

path pt1=scale(2cm)*unitcircle;
path pt2=scale(1cm)*unitcircle;
path pt3=shift(0,.5cm)*pt2;

filldraw(pt1^^pt2^^pt3,evenodd+yellow+.9white);

🔗generalities-fig193

Figure generalities 193 Generated with Asymptote

size(0,0);

path pt1=scale(2cm)*unitcircle;
path pt2=scale(1cm)*unitcircle;
path pt3=shift(0,1.5cm)*pt2;

filldraw(pt1^^pt2^^pt3,evenodd+yellow+.9white);

🔗geometry-fig013

Figure geometry 013 Generated with Asymptote

import geometry;
size(10cm,0);

currentcoordsys=cartesiansystem((2,1),i=(1,0.5),j=(-1,1));
coordsys Rp=currentcoordsys;
coordsys Rs=cartesiansystem((-1,2),i=(-1,0.5),j=(-1,-1));
coordsys R=defaultcoordsys;

show("$O$","$\vec{\imath}$", "$\vec{\jmath}$", R);
show("$O'$","$\vec{u}$","$\vec{v}$", Rp, xpen=invisible);
show("$O''$", "$\vec{u'}$", "$\vec{v'}$", Rs, xpen=invisible);

pair a=(0.5,0.5);
pair b=(-0.5,-1);

point A=point(R,a), B=point(R,b);
dot("$A$",A,S); dot("$B$",B,S);
line l=line(A,B);

point Ap=a, Bp=b;
dot("$A'$",Ap); dot("$B'$",Bp,SE);
line lp=line(Ap,Bp);

point As=point(Rs,a), Bs=point(Rs,b);
dot("$A''$",As,S); dot("$B''$",Bs,SE);
line ls=line(As,Bs);

draw(l^^lp^^ls);

dot(intersectionpoint(l,lp),2mm+red);
dot(intersectionpoint(l,ls),2mm+red);
dot(intersectionpoint(lp,ls),2mm+red);

🔗geometry-fig014

Figure geometry 014 Generated with Asymptote

include fig0130;

point w=l.A+1.5*l.v;
draw(Label("$w$",EndPoint),l.A--w,Arrow);

point wp=lp.A+1.5*lp.v;
draw(Label("$w'$",EndPoint),lp.A--wp,Arrow);

point ws=ls.A+1.5*ls.v;
draw(Label("$w''$",EndPoint),ls.A--ws,Arrow);

int n=64;
real step=2pi/n;

for (int i=0; i<n; ++i) {
  point p=B+point(R,R.polar(1,step*i));
  dot(p,sameside(p,w,l) ? black : blue);
  
  point p=Ap+point(Rp,Rp.polar(1,step*i));
  dot(p,sameside(p,wp,lp) ? black : blue);

  point p=As+point(Rs,Rs.polar(1,step*i));
  dot(p,sameside(p,ws,ls) ? black : blue);
}

🔗geometry-fig015

Figure geometry 015 Generated with Asymptote

Show geometry/fig0150.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Geometry.asy
Tags : #Geometry | #Line | #Intersection | #Path

size(12cm,0);
import geometry;
import base_pi;
dotfactor*=2;

currentcoordsys=cartesiansystem((0,0),i=(1,0.5),j=(-1,1));
coordsys Rp=currentcoordsys;
show("$O'$","$\vec{u}$","$\vec{v}$", Rp, xpen=invisible);

path cle=randompath(20);
draw(cle);

point A=(0,1.5), B=(1,-0.5);

line l=line(A,B);
draw(l);

/*<asyxml><view file="modules/geometry.asy" type="pair[]" signature="intersectionpoints(line,path)"/></asyxml>*/
dot(intersectionpoints(l,cle));

🔗geometry-fig017

Figure geometry 017 Generated with Asymptote

unitsize(1cm);
import geometry;
dotfactor*=1.5;
linemargin=5mm;

// currentcoordsys=cartesiansystem((2,1),i=(1,0.5),j=(-1,1));
show(currentcoordsys);

point A=(-3,-1), B=(3,4);
line l1=line(A,B);

draw(l1,red);
dot("$A$",A,SE);
dot("$B$",B,NW);

point M=(2,-2);
dot("$M$",M);

/*<asyxml><view file="modules/geometry.asy" type="line" signature="parallel(point,line)"/></asyxml>*/
draw(parallel(M,l1),red);

/*<asyxml><view file="modules/geometry.asy" type="line" signature="perpendicular(point,line)"/></asyxml>*/
line perp=perpendicular(M,l1);
draw(perp);

/*<asyxml><view file="modules/geometry.asy" type="point" signature="intersectionpoint(line,line)"/></asyxml>*/
point interp=intersectionpoint(l1,perp);
dot(interp,green);

/*<asyxml><view file="modules/geometry.asy" type="void" signature="markrightangle(picture,point,point,point,real,pen,margin,filltype)"/></asyxml>*/
markrightangle(l1.A,interp,rotate(180,interp)*M,size=5mm);

draw(box((-5,-5),(5,5)),invisible);

🔗geometry-fig022

Figure geometry 022 Generated with Asymptote

unitsize(2cm);
import geometry;

currentcoordsys=cartesiansystem((2,1),i=(1,0.25),j=(-0.25,.75));
show(lo=Label("$O$",align=SE+0.5E), currentcoordsys);

pair A=(1,1), B=(2,2);
line l1=line(A,B);
draw("$(l_1)$",l1);

line l2=rotate(100,(3,3))*l1;
draw("$(l_2)$",l2);
write(locate(intersectionpoint(l1,l2)));
/*<asyxml><view file="modules/geometry.asy" type="line" signature="bisector(line,line,real,bool)"/></asyxml>*/
line bis=bisector(l1,l2);
draw(bis);

line Bis=bisector(l1,l2,90);
draw(Bis,0.8*red);
markangleradiusfactor*=5;

/*<asyxml><view file="modules/geometry.asy" type="void" signature="markangle(picture,Label,int,real,real,line,line,arrowbar,pen,filltype,margin,marker)"/></asyxml>*/
markangle(2, l1, l2, StickIntervalMarker(2,2,true));
markangle(2, reverse(l2), l1, radius=1.25*markangleradius(), StickIntervalMarker(2,1,true));

/*<asyxml><view file="modules/geometry.asy" type="bool" signature="concurrent(...line[])"/></asyxml>*/
if (concurrent(bis,l1,l2,Bis)) label("Concurrent",(3,3), dir(135));

draw(box(locate((-1,0)),locate((5,5))),invisible);

🔗geometry-fig023

Figure geometry 023 Generated with Asymptote

Show geometry/fig0230.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Geometry.asy
Tags : #Geometry | #Coords system | #Line | #Intersection

import geometry;
size(12cm,0);

currentcoordsys=cartesiansystem((2,1),i=expi(pi/18)*(1,0),j=expi(pi/18)*(0,1));
show(currentcoordsys,xpen=invisible);

point A=(-1.5,-1);
point C=(-1,1);
point B=(-1,0);

dot("$A$", A, 2W);
dot("$B$", B, 2E);

line l1=hline()+C;
draw("$(l_1)$", l1, blue);
dot("$C$", C, NE);

line l2=line(A, B, false);
draw(Label("$(AB]$",Relative(.25),SE), l2, green);

/*<asyxml><view file="modules/geometry.asy" type="line" signature="complementary(explicit line)"/></asyxml>*/
draw("Complementary of $(AB]$", complementary(l2), dotted+roundcap);

point p=intersectionpoint(l1,l2);

/*<asyxml><view file="modules/geometry.asy" type="bool" signature="defined(pair)"/></asyxml>*/
string s="$(l_1)$" + (defined(p) ? " intersects " : " does not intersect ") + "$(AB]$";
label(s, A+1.75*l2.u,W);

draw(box(locate((-2,-2)),locate((2,2))), invisible);

🔗geometry-fig035

Figure geometry 035 Generated with Asymptote

Show geometry/fig0350.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Geometry.asy
Tags : #Geometry | #Circle | #Line | #Intersection

import geometry;
size(8cm,0);

currentcoordsys=cartesiansystem((2,1),i=(1,0.5),j=(-0.25,.75));
show(currentcoordsys, xpen=invisible);

point A=(-1,0);
point B=(0.5,-3sin(2));
dot("$A$",A,S,red);
dot("$B$",B,N,red);

line l=line(A,B);
circle c=circle((point)(0,-sqrt(2)/2),exp(1));
draw(l);
draw(c);

/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(line,circle)"/></asyxml>*/
point[] inter=intersectionpoints(l,c);
dot("$M$", inter[0], 2S, red);
dot("$N$", inter[1], 2N+0.5W, red);

🔗geometry-fig036

Figure geometry 036 Generated with Asymptote

Show geometry/fig0360.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Geometry.asy
Tags : #Geometry | #Line | #Ellipse | #Intersection

import geometry;
size(8cm,0);

currentcoordsys=cartesiansystem((2,1),i=(1,0.5),j=(-0.25,.75));
show(currentcoordsys);

point A=(-1,0);
point B=(0.5,-3sin(2));
dot("$A$",A,S,red);
dot("$B$",B,N,red);

line l=line(A,B);
ellipse el=ellipse((0,-sqrt(2)/2),3,2,90);
draw(l);
draw(el,Arrow);

/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(line,ellipse)"/></asyxml>*/
point[] inter=intersectionpoints(l,el);
dot("$M$", inter[0], 4N+2W, red);
dot("$N$", inter[1], 2S+0.5E, red);

🔗geometry-fig037

Figure geometry 037 Generated with Asymptote

Show geometry/fig0370.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Geometry.asy
Tags : #Geometry | #Line | #Parabola | #Intersection

import geometry;
size(10cm);

// currentcoordsys=cartesiansystem((2,1),i=(1,0.5),j=(-0.25,.75));
// show(currentcoordsys);

point A=(-1,-1);
point B=(2,1);
dot("$A$",A,S,red);
dot("$B$",B,N,red);

line l=line(A,B);
draw(l);

point F=(2,-1.5);
dot("$F$",F,N);

parabola p=parabola(F,0.2,110);
draw(p);

/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(line,parabola)"/></asyxml>*/
point[] inter=intersectionpoints(l,p);
dot("$M$", inter[0], 2N+E, red);
dot("$N$", inter[1], S+2E, red);

🔗geometry-fig038

Figure geometry 038 Generated with Asymptote

Show geometry/fig0380.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Geometry.asy
Tags : #Geometry | #Line | #Intersection | #Hyperbola

import geometry;
size(10cm);

// currentcoordsys=cartesiansystem((2,1),i=(1,0.5),j=(-0.25,.75));
// show(currentcoordsys);

// Enlarge the bounding box of the current picture
draw(box((-6,-5), (10,2)), invisible);

point A=(-2,-2);
point B=(2,-3);
dot("$A$",A,N,red);
dot("$B$",B,S,red);

line l=line(A,B);
draw(l);

point C=(2,-1.5);
dot("$C$",C,N);

hyperbola h=hyperbola(C,sqrt(2),sqrt(2)/2,0);
draw(h);

/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(line,hyperbola)"/></asyxml>*/
point[] inter=intersectionpoints(l,h);
dot("$M$", inter[0], 2N+E, red);
dot("$N$", inter[1], 2S+E, red);

🔗geometry-fig039

Figure geometry 039 Generated with Asymptote

Show geometry/fig0390.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Geometry.asy
Tags : #Geometry | #Line | #Intersection | #Circle

import geometry;

size(8cm,0);

currentcoordsys=cartesiansystem((0,0),i=(1,1),j=(-0.5,.75));
show(currentcoordsys);

point A=(-0.5,.75);
point B=(1,1);
dot("$A$",A,SE);
dot("$B$",B,NW);

line l=line(A,B,false);
line ll=hline()+B;

circle c=circle((point)(0.5,0.5),2);
draw(l^^ll);
draw(complementary(l),dashed+grey);
draw(c);

dotfactor*=2;

/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(line,circle)"/></asyxml>*/
dot(intersectionpoints(l,c),red);
dot(intersectionpoints(ll,c),red);

🔗geometry-fig040

Figure geometry 040 Generated with Asymptote

Show geometry/fig0400.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Geometry.asy
Tags : #Geometry | #Line | #Intersection | #Ellipse

import geometry;

size(8cm,0);

currentcoordsys=cartesiansystem((0,0),i=(1,1),j=(-0.5,.75));
show(currentcoordsys);

point A=(-0.5,.75);
point B=(1,1);
dot("$A$",A,SE);
dot("$B$",B,NW);

line l=line(A,B,false);
line ll=hline()+B;

ellipse el=ellipse((point)(0.5,0.5),3,2);
draw(l^^ll);
draw(complementary(l),dashed+grey);
draw(el);

dotfactor*=2;

/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(line,ellipse)"/></asyxml>*/
dot(intersectionpoints(l,el),red);
dot(intersectionpoints(ll,el),red);

🔗geometry-fig041

Figure geometry 041 Generated with Asymptote

Show geometry/fig0410.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Geometry.asy
Tags : #Geometry | #Line | #Intersection | #Parabola

import geometry;
size(10cm);

// currentcoordsys=cartesiansystem((2,1),i=(1,0.5),j=(-0.25,.75));
// show(currentcoordsys);

point A=(-1,-1);
point B=(2,1);
dot("$A$",A,S,red);
dot("$B$",B,NW,red);

line l=line(A,B,false);
line ll=hline()+0.5*B;
draw(l^^ll);
draw(complementary(l),dashed+grey);

point F=(2,-1.5);
dot("$F$",F,N);

parabola p=parabola(F,0.2,110);
draw(p);

dotfactor*=2;

/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(line,parabola)"/></asyxml>*/
dot(intersectionpoints(l,p), red);
dot(intersectionpoints(ll,p), red);

🔗geometry-fig042

Figure geometry 042 Generated with Asymptote

Show geometry/fig0420.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Geometry.asy
Tags : #Geometry | #Line | #Intersection | #Circle

import geometry;
size(10cm,0);

// currentcoordsys=cartesiansystem((0,0),i=(1,1),j=(-0.5,.75));
// show(currentcoordsys);

point A=(-1,-1);
point B=(0.75,0.5);
dot("$A$",A,NW,red);
dot("$B$",B,N,red);

circle c1=circle(A,1.5);
circle c2=circle(B,2);
draw(c1^^c2);

/*<asyxml><view file="modules/geometry.asy" type="line" signature="radicalline(circle,circle)"/></asyxml>*/
draw(radicalline(c1,c2));
/*<asyxml><view file="modules/geometry.asy" type="point" signature="radicalcenter(circle,circle)"/></asyxml>*/
dot(radicalcenter(c1,c2));

dotfactor*=2;

/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(circle,circle)"/></asyxml>*/
point[] inter=intersectionpoints(c1,c2);
dot("$M$", inter[0], 2SW, red);
dot("$N$", inter[1], 2NE, red);

🔗geometry-fig043

Figure geometry 043 Generated with Asymptote

Show geometry/fig0430.asy on Github.
Generated with Asymptote 3.00-0.
Categories : Examples 2D | Geometry.asy
Tags : #Geometry | #Intersection | #Ellipse

import geometry;
size(10cm,0);

// currentcoordsys=cartesiansystem((0,0),i=(1,1),j=(-0.5,.75));
// show(currentcoordsys);

point C=(0,0);
point Cp=(0.5,0.5);
dot("$C$",C,NW,red);
dot("$C'$",Cp,N,red);

ellipse el1=ellipse(C,2,1);
ellipse el2=ellipse(Cp,3,1,40);
draw(el1^^el2);

dotfactor*=2;

/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(ellipse,ellipse)"/></asyxml>*/
point[] inter=intersectionpoints(el1,el2);
dot(inter);

🔗geometry-fig044

Figure geometry 044 Generated with Asymptote

import geometry;
size(10cm,0);

// currentcoordsys=cartesiansystem((0,0),i=(1,0.25),j=(-0.5,.75));
show(currentcoordsys, xpen=invisible);

point A=(-1,-1);
point B=(0.75,0.5);
dot("$A$",A,NW,red);
dot("$B$",B,N,red);

circle c1=circle(A,1.5);
circle c2=circle(B,2);
draw(c1^^c2);

point[] inter=intersectionpoints(c1,c2);
dot("$M$", inter[0], 2NW, red);

/*<asyxml><view file="modules/geometry.asy" type="line" signature="tangent(circle,point)"/></asyxml>*/
draw(tangent(c1,inter[0]), grey);
draw(tangent(c2,inter[0]), grey);

/*<asyxml><view file="modules/geometry.asy" type="line" signature="tangent(circle,abscissa)"/></asyxml>*/
draw(tangent(c2,angabscissa(135)), grey);

🔗geometry-fig045

Figure geometry 045 Generated with Asymptote

import geometry;
size(10cm,0);

point c2=(13,5);
real r=4, R=abs(c2)-r;

circle[] C={circle(origin, 4), circle(c2,R)};
draw(C[0]^^C[1], blue);

segment s=segment(origin, c2);
draw(s, red, dot);

/*<asyxml><view file="modules/geometry.asy" type="point" signature="curpoint(line,real)"/></asyxml>*/
point T=curpoint(s,r/(r-R)*abs(c2));
dot(T);
/*<asyxml><view file="modules/geometry.asy" type="line" signature="tangents(circle,point)"/></asyxml>*/
line[] tgt=tangents(C[1], T);
draw(tgt);

point[][] t= new point[2][2];
for (int i=0; i < 2 ; ++i)
  for (int j=0; j < 2; ++j) {
    /*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(line,circle)"/></asyxml>*/
    t[i][j]=intersectionpoints(C[i],tgt[j])[0];
    draw(C[i].C--t[i][j], dot);
    markrightangle(T, t[i][j], C[i].C, size=(i == 0 ? 2mm : 0));
  }

addMargins(cm/2,cm/2);

🔗geometry-fig046

Figure geometry 046 Generated with Asymptote

import geometry;
size(10cm,0);

// currentcoordsys=cartesiansystem((0,0),i=(1,0.5),j=(-0.5,.75));
show(currentcoordsys, xpen=invisible);

point A=(-1,-1);
point B=(0.75,0.5);
dot("$A$",A,NW,red);
dot("$B$",B,N,red);

ellipse el1=ellipse(A,2,1.5);
ellipse el2=ellipse(B,3,2);
draw(el1);
draw(el2,Arrow);

point[] inter=intersectionpoints(el1,el2);
dot("$M$", inter[0], 2NW, red);

/*<asyxml><view file="modules/geometry.asy" type="line[]" signature="tangents(ellipse,point)"/></asyxml>*/
draw(tangents(el1,inter[0]), grey);
draw(tangents(el2,inter[0]), grey);

/*<asyxml><view file="modules/geometry.asy" type="line" signature="tangent(ellipse,abscissa)"/></asyxml>*/
draw(tangent(el2,angabscissa(90)), grey);

🔗geometry-fig047

Figure geometry 047 Generated with Asymptote

import geometry;
size(12cm);

// currentcoordsys=cartesiansystem((0,0),i=(1,0.5),j=(-0.5,.75));
// show(currentcoordsys, xpen=invisible);

point F1=(0,0);
dot("$F1$",F1,NW);
point F2=(-0.25,0.5);
dot("$F2$",F2,SE);

parabola p=parabola(F1, 0.1, 120);
draw(p, bp+red);

parabola pp=parabola(F2, 0.06, 280);
draw(pp, bp+blue);

abscissa x=angabscissa(180);
dot(point(p,x));
/*<asyxml><view file="modules/geometry.asy" type="line" signature="tangent(parabola,abscissa)"/></asyxml>*/
draw(tangent(p,x), 0.8*red);

point[] P=intersectionpoints(p,pp);
dot(P);

/*<asyxml><view file="modules/geometry.asy" type="line[]" signature="tangents(parabola,point)"/></asyxml>*/
draw(tangents(p,P[0]), 0.8*red);
draw(tangents(pp,P[0]), 0.8*blue);

// Enlarge the bounding box
draw(box((-1,-0.4), (0.5,0.6)),invisible);

🔗geometry-fig048

Figure geometry 048 Generated with Asymptote

import geometry;
size(10cm);

point C=(4,2);
dot("$C$",C,E+NE,red);

hyperbola h=hyperbola(C,1.5,1,-20);
draw(h, linewidth(bp));

/*<asyxml><view file="modules/geometry.asy" type="line" signature="tangent(hyperbola,abscissa)"/></asyxml>*/
line l=tangent(h,angabscissa(85));
draw(l, grey);
dot(intersectionpoints(h,l));

l=tangent(h,angabscissa(0,fromCenter));
draw(l, grey);
dot(intersectionpoints(h,l));

// Enlarge the bounding box of the current picture.
draw(box((-1,-0.5), (9,4)), invisible);

🔗geometry-fig049

Figure geometry 049 Generated with Asymptote

import geometry;
size(12cm);

point C=(0,0);
dot(C);

hyperbola[] h;
h[0]=hyperbola(C,2,2);
h[1]=hyperbola(C,1.5,1);

draw(h[0], 2bp+0.8*red);
draw(h[1], 2bp+0.8*blue);

point[] P=intersectionpoints(h[0],h[1]);

line[] l;
for (int i=0; i < P.length; ++i) {
  for (int j=0; j < 2; ++j) {
    /*<asyxml><view file="modules/geometry.asy" type="line[]" signature="tangents(hyperbola,point)"/></asyxml>*/
    l=tangents(h[j],P[i]);
    draw(l[0], j == 0 ? red : blue);
  }
}

dot(P, yellow);

// Enlarge the bounding box of the current picture.
draw(box((-4,-3), (4,3)), invisible);

🔗geometry-fig050

Figure geometry 050 Generated with Asymptote

import geometry;
size(10cm,0);

currentcoordsys=cartesiansystem((0,0),i=(1,0.5),j=(-0.5,.75));
show(currentcoordsys, xpen=invisible);

point A=(2.5,-1);
point B=A+(3,1);
dot("$A$",A,SW);
dot("$B$",B,2N+0.5W);

circle c1=circle(A,1.5);
draw(c1);

/*<asyxml><view file="modules/geometry.asy" type="line[]" signature="tangents(circle,point)"/></asyxml>*/
line[] tgt=tangents(c1,B);
draw(tgt,red);
/*<asyxml><view file="modules/geometry.asy" type="circle" signature="circle(point,point)"/></asyxml>*/
draw(circle(B,A),grey);

// dot(intersectionpoints(c1,circle(B,A)),red);
for (int i=0; i<tgt.length; ++i) {
  dot(intersectionpoints(c1,tgt[i]),2mm+red);
}

🔗geometry-fig051

Figure geometry 051 Generated with Asymptote

import geometry;
size(12cm,0);

// currentcoordsys=cartesiansystem((0,0),i=(1,0.5),j=(-0.5,.75));
// show(currentcoordsys, xpen=invisible);

point A=(2.5,-1);
dot("$A$",A,SW);
ellipse el1=ellipse(A,2,1,10);
draw(el1);

circle C=circle(A,3);
draw(C);
for (int i=0; i < 360; i+=90) {

  point B=point(C,angabscissa(i));
  dot("$B$",B,locate(unit(B-A)));


  line[] tgt=tangents(el1,B);
  draw(tgt,0.8*red);

  for (int i=0; i < tgt.length; ++i) {
    dot(intersectionpoints(el1,tgt[i]),blue);
  }

}

🔗geometry-fig052

Figure geometry 052 Generated with Asymptote

import geometry;
size(12cm,0);

// currentcoordsys=cartesiansystem((0,0),i=(1,0.5),j=(-0.5,.75));
// show(currentcoordsys, xpen=invisible);

point F=(0,0);
dot("$F$", F, SW);
parabola p=parabola(F, 0.1, 30);
draw(p);

point C=shift(2*(p.V-p.F))*p.V;
circle cle=circle(C, 0.2);
draw(cle);
for (int i=0; i < 360; i+=90) {

  point M=point(cle, angabscissa(i));
  dot("$M$", M, locate(unit(M-C)));

  line[] tgt=tangents(p, M);
  draw(tgt, 0.8*red);

  for (int i=0; i < tgt.length; ++i) {
    dot(intersectionpoints(p, tgt[i]), blue);
  }
}

🔗geometry-fig076

Figure geometry 076 Generated with Asymptote

import geometry;
size(12cm);

// currentcoordsys=cartesiansystem((2,1),i=(1,0.5),j=(-0.25,0.75));
// currentcoordsys=cartesiansystem((2,1),i=rotate(45)*(1,0),j=rotate(45)*(0,1));
// show(currentcoordsys);

conic co[];
co[0]=circle((point)(0,0),1);
/*<asyxml><view file="modules/geometry.asy" type="void" signature="draw(picture,Label,explicit conic,align,pen,arrowbar,arrowbar,margin,Label,marker)"/></asyxml>*/
draw(co[0]);

co[1]=ellipse((point)(0,0),4,1);
draw(co[1]);

co[2]=parabola((0,0),1,90);
draw(co[2]);

hyperbola h=hyperbola((-1,0),(1,0),1.2,byvertices);
co[3]=h;
draw(co[3]);
draw(h.A1,grey);
draw(h.A2,grey);

dotfactor *= 1;

for (int i=0; i < 4; ++i) {
  dot(intersectionpoints(h.A1,co[i]),blue);
  dot(intersectionpoints(h.A2,co[i]),blue);
  for (int j=i+1; j < 4; ++j)
    /*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(conic,conic)"/></asyxml>*/
    dot(intersectionpoints(co[i],co[j]), red);
}

🔗geometry-fig096

Figure geometry 096 Generated with Asymptote

import geometry;
size(8cm);

// currentcoordsys=cartesiansystem((1,2),i=(1,0.5),j=(-0.5,.75));
show(currentcoordsys, xpen=invisible);

point A=(-1,0) ; dot("$A$",A,S);
point B=(1,1)  ; dot("$B$",B,S);
point C=(0,0)  ;
point D=(1,-1) ; dot("$D$",D,SW);

arc c=arc(circle(C,2), 0, 270);
draw(complementary(c),dashed+grey);

line l1=line(A,B); draw(l1);
line l2=line(C,D); draw(l2);

point[] J=intersectionpoints(l1,c);
point[] K=intersectionpoints(l2,c);

/*<asyxml><view file="modules/geometry.asy" type="arc" signature="arc(explicit arc,point,point)"/></asyxml>*/
draw(arc(c,K[0],J[0]),2mm+0.8yellow);
draw(arc(c,J[1],K[0]),2mm+0.8red);
/*<asyxml><view file="modules/geometry.asy" type="arc" signature="arc(explicit arc,abscissa,abscissa)"/></asyxml>*/
draw(arc(c,relabscissa(c,J[0]),relabscissa(1)),2mm+0.8green);
draw(arc(c,relabscissa(0),relabscissa(c,J[1])),2mm+0.8blue);

dot("$J_0$",J[0],2NW);
dot("$J_1$",J[1],2N);
dot("$K_0$",K[0],2W);

draw(c, 1mm+white);

🔗geometry-fig097

Figure geometry 097 Generated with Asymptote

import geometry;
size(8cm);

// currentcoordsys=cartesiansystem((1,2),i=(1,0.5),j=(-0.5,.75));
show(currentcoordsys, xpen=invisible);

point A=(-1,0) ; dot("$A$",A,S);
point B=(1,1)  ; dot("$B$",B,S);
point C=(0,0)  ;
point D=(1,-1) ; dot("$D$",D,SW);

arc c=arc(ellipse(C,2,1,20), 0, 270);
draw(complementary(c),dashed+grey);

line l1=line(A,B); draw(l1);
line l2=line(C,D); draw(l2);

point[] J=intersectionpoints(l1,c);
point[] K=intersectionpoints(l2,c);

/*<asyxml><view file="modules/geometry.asy" type="arc" signature="arc(explicit arc,point,point)"/></asyxml>*/
draw(arc(c,J[0],K[0]),2mm+0.8yellow);
draw(arc(c,K[0],J[1]),2mm+0.8red);
/*<asyxml><view file="modules/geometry.asy" type="arc" signature="arc(explicit arc,abscissa,abscissa)"/></asyxml>*/
draw(arc(c,relabscissa(c,J[1]),relabscissa(1)),2mm+0.8green);
draw(arc(c,relabscissa(0),relabscissa(c,J[0])),2mm+0.8blue);

dot("$J_0$",J[0],2N);
dot("$J_1$",J[1],N+2W);
dot("$K_0$",K[0],2N);

draw(c, 1mm+white);

🔗geometry-fig101

Figure geometry 101 Generated with Asymptote

import geometry;
size(8cm,0);

currentcoordsys=cartesiansystem((1,2),i=(1,0.5),j=(-0.5,.75));
show(currentcoordsys, xpen=invisible);

real R=2;

point A=(1,1);
dot("$A$", A, S, red);
point B=A+(2,1);
dot("$B$", B, N, blue);

arc a=arc(circle(A,R), -40, 180);
arc b=arc(circle(B,R), -45, 220);
line l=line(A,B);

draw(a,red);
draw(b,blue);
draw(l);

/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(arc,arc)"/></asyxml>*/
point[] inter=intersectionpoints(a,b);
dot(inter);

/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(line,arc)"/></asyxml>*/
point[] inter=intersectionpoints(l,a);
dot(inter);

point[] inter=intersectionpoints(l,b);
dot(inter);

🔗geometry-fig102

Figure geometry 102 Generated with Asymptote

import geometry;
size(8cm,0);

// currentcoordsys=cartesiansystem((1,2),i=(1,0.5),j=(-0.5,.75));
// show(currentcoordsys, xpen=invisible);

real R=2;

point A=(1,1);
dot("$A$", A, S, red);
point B=A+(2,1);
dot("$B$", B, N, blue);

arc a=arc(ellipse(A,R,R/2), -40, 180);
arc b=arc(ellipse(B,R,R/2), -45, 220);

line l=line(A,B);

draw(a,red);
draw(b,blue);
draw(l);

/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(arc,arc)"/></asyxml>*/
point[] inter=intersectionpoints(a,b);
dot(inter);

/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(line,arc)"/></asyxml>*/
point[] inter=intersectionpoints(l,a);
dot(inter);

point[] inter=intersectionpoints(l,b);
dot(inter);

🔗geometry-fig103

Figure geometry 103 Generated with Asymptote

import geometry;
size(8cm,0);

currentcoordsys=cartesiansystem((1,2),i=(1,0.5),j=(-0.5,.75));
show(currentcoordsys, xpen=invisible);

real R=2;

point A=(1,1.5);
dot("$A$",A,S,red);
point B=A+(2,1);
dot("$B$",B,S,blue);

arc a=arc(circle(A,R),-40,180);
arc b=arc(circle(B,R),-45,220);

draw(a,red);
draw(b,blue);

point M=intersectionpoints(a,b)[0];
dot(M);

/*<asyxml><view file="modules/geometry.asy" type="line" signature="tangent(explicit arc,point)"/></asyxml>*/
draw(tangent(a,M), grey);
draw(tangent(b,M), grey);

/*<asyxml><view file="modules/geometry.asy" type="line" signature="tangent(explicit arc,abscissa)"/></asyxml>*/
draw(tangent(a,angabscissa(45)), grey);

🔗geometry-fig104

Figure geometry 104 Generated with Asymptote

import geometry;
size(10cm,0);

// currentcoordsys=cartesiansystem((1,2),i=(1,0.5),j=(-0.5,.75));
// show(currentcoordsys, xpen=invisible);

real R=2;

point A=(1,1.5);
dot("$A$",A,S,red);
point B=A+(2.5,1);
dot("$B$",B,E,blue);

arc a=arc(ellipse(A,R,R/2,30),-40,180);
// ellispenodesnumberfactor=400;
arc b=arc(ellipse(B,2R,R/2,-10),-30,180);

draw(a,red);
draw(b,blue);

point M=intersectionpoints(a,b)[0];
dot(M);

/*<asyxml><view file="modules/geometry.asy" type="line" signature="tangent(explicit arc,point)"/></asyxml>*/
draw(tangent(a,M), grey);
draw(tangent(b,M), grey);

/*<asyxml><view file="modules/geometry.asy" type="line" signature="tangent(explicit arc,abscissa)"/></asyxml>*/
draw(tangent(a,angabscissa(45)), grey);

🔗geometry-fig105

Figure geometry 105 Generated with Asymptote

import geometry;
size(8cm,0);

// currentcoordsys=cartesiansystem((1,2),i=(1,0.5),j=(-0.5,.75));
// show(currentcoordsys, xpen=invisible);

point A=(0.25,0.25);
point B=A+(1,0.25);
dot("$A$",A,S,red);
dot("$B$",B,N,red);

segment s=segment(A,B);
line bis=bisector(s);

draw(s,StickIntervalMarker(2,2));
draw(bis);

/*<asyxml><view file="modules/geometry.asy" type="path" signature="compassmark(pair,pair,real,real)"/></asyxml>*/
draw(compassmark(A, point(bis,0.75), position=0.25,angle=25), grey);
draw(compassmark(B, point(bis,0.75), position=0.75,angle=25), grey);

/*<asyxml><view file="modules/geometry.asy" type="point" signature="point(line,real)"/></asyxml>*/
draw(compassmark(A, point(bis,0.25), position=0.5,angle=15), grey);
draw(compassmark(B, point(bis,0.25), position=0.5,angle=15), grey);

🔗geometry-fig115

Figure geometry 115 Generated with Asymptote

import geometry;
size(8cm);

// currentcoordsys=cartesiansystem((2,1),i=(1,0.5),j=(-0.25,.75));
// show(currentcoordsys);

dotfactor *=1.5;
triangle t=triangleabc(3,4,5);
drawline(t, linewidth(bp));
label(t, alignFactor=3);

line l=line((-1,-2), (1,0.5));
draw(l, 0.8*red);
/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(triangle,line,bool)"/></asyxml>*/
dot(intersectionpoints(t,l), 0.8*red);

circle C=2*circle(t);
draw(C, 0.8*blue);
/*<asyxml><view file="modules/geometry.asy" type="point[]" signature="intersectionpoints(triangle,conic,bool)"/></asyxml>*/
dot(intersectionpoints(t,C, true), 0.8*blue);

🔗solids-fig012

Figure solids 012 Generated with Asymptote

import solids;

size(10cm, 0);
currentprojection=orthographic(-50, 100, 40);

//Draw right angle (MA, MB) in 3D
void drawrightangle(picture pic=currentpicture,
                    triple M, triple A, triple B,
                    real radius=0,
                    pen p=currentpen,
                    pen fillpen=nullpen,
                    projection P=currentprojection)
{
  p=linejoin(0)+linecap(0)+p;
  if (radius==0) radius=arrowfactor*sqrt(2);
  transform3 T=shift(-M);
  triple OA=radius/sqrt(2)*unit(T*A),
    OB=radius/sqrt(2)*unit(T*B),
    OC=OA+OB;
  path3 _p=OA--OC--OB;
  picture pic_;
    draw(pic_, _p, p=p);
    if (fillpen!=nullpen) draw(pic_, surface(O--_p--cycle), fillpen);
  add(pic, pic_, M);
}

// *...............Construction starts here................*

real r=1, h=.75;
real gle=60;
real gleA=20;
transform3 tR=rotate(gle, Z);
transform3 tT=shift((0, 0, -h));

triple H=(0, 0, h),//the label is O in the picture.
  A=rotate(gleA, Z)*(0, r, h),
  F=tR*A,
  B=tR*F,
  D=tT*A,
  C=tT*B,
  Ei=intersectionpoint(H--F, A--B);

revolution r=cylinder(O, r, h, Z);
// draw(surface(r));
draw(r);

draw(O--H, dashed);
draw(O--D--C--cycle^^O--H^^B--C, dashed);

drawrightangle(Ei, H, B, fillpen=black);

dot(Label("$O'$", align=invert(NE+E, O)), O);
// layer();
draw(surface(A--B--C--D--cycle), lightgrey+opacity(.5));

dot(Label("$A$", align=NW), A);
dot(Label("$B$", align=N), B);
dot(Label("$C$", align=S), C);
dot(Label("$D$", align=NW), D);
dot(Label("$E$", align=S), Ei);
dot(Label("$F$", align=S), F);
dot(Label("$O$", align=N), H);

draw(H--B--F--A--cycle^^H--F^^A--B^^A--D);

🔗three-fig005

Figure three 005 Generated with Asymptote

import three; import math;
size(8cm,0);
currentprojection=obliqueX;

real h=2;
triple A =(0,0,h), B=(h,0,0), C=(0,h,0), D=(0,0,0);
triple Ip=midpoint(A--C), J=midpoint(A--B);
triple K=shift((0,0,-0.25*h))*A;

triple M=interp(K,J,intersect(K,J,normal(new triple[]{B,C,D}),D));
triple Np=interp(K,Ip,intersect(K,Ip,normal(new triple[]{B,C,D}),D));

dot("$A$", A, align=Z);  dot("$B$", B, align=S);
dot("$C$", C, align=S);  dot("$D$", D, align=W);
dot("$I$", Ip, align=N); dot("$J$", J, align=W);
dot("$K$", K, align=NE); dot("$M$", M, align=SE);
dot("$N$", Np, align=S);

draw(A--B--C--cycle^^B--M^^C--Np^^J--M^^Ip--Np);
draw(A--D--C^^D--B^^J--K^^K--Ip, dashed);